diff --git a/openapi3filter/issue639_test.go b/openapi3filter/issue639_test.go
new file mode 100644
index 000000000..2caf1bd14
--- /dev/null
+++ b/openapi3filter/issue639_test.go
@@ -0,0 +1,100 @@
+package openapi3filter
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/getkin/kin-openapi/openapi3"
+	"github.com/getkin/kin-openapi/routers/gorillamux"
+)
+
+func TestIssue639(t *testing.T) {
+	loader := openapi3.NewLoader()
+	ctx := loader.Context
+	spec := `
+    openapi: 3.0.0
+    info:
+     version: 1.0.0
+     title: Sample API
+    paths:
+     /items:
+      put:
+        requestBody:
+         content:
+          application/json:
+            schema:
+              properties:
+                testWithdefault:
+                  default: false
+                  type: boolean
+                testNoDefault:
+                  type: boolean
+              type: object
+        responses:
+          '200':
+           description: Successful respons
+`[1:]
+
+	doc, err := loader.LoadFromData([]byte(spec))
+	require.NoError(t, err)
+
+	err = doc.Validate(ctx)
+	require.NoError(t, err)
+
+	router, err := gorillamux.NewRouter(doc)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name               string
+		options            *Options
+		expectedDefaultVal interface{}
+	}{
+		{
+			name: "no defaults are added to requests",
+			options: &Options{
+				SkipSettingDefaults: true,
+			},
+			expectedDefaultVal: nil,
+		},
+
+		{
+			name:               "defaults are added to requests",
+			expectedDefaultVal: false,
+		},
+	}
+
+	for _, testcase := range tests {
+		t.Run(testcase.name, func(t *testing.T) {
+			body := "{\"testNoDefault\": true}"
+			httpReq, err := http.NewRequest(http.MethodPut, "/items", strings.NewReader(body))
+			require.NoError(t, err)
+			httpReq.Header.Set("Content-Type", "application/json")
+			require.NoError(t, err)
+
+			route, pathParams, err := router.FindRoute(httpReq)
+			require.NoError(t, err)
+
+			requestValidationInput := &RequestValidationInput{
+				Request:    httpReq,
+				PathParams: pathParams,
+				Route:      route,
+				Options:    testcase.options,
+			}
+			err = ValidateRequest(ctx, requestValidationInput)
+			require.NoError(t, err)
+			bodyAfterValidation, err := ioutil.ReadAll(httpReq.Body)
+			require.NoError(t, err)
+
+			raw := map[string]interface{}{}
+			err = json.Unmarshal(bodyAfterValidation, &raw)
+			require.NoError(t, err)
+			require.Equal(t, testcase.expectedDefaultVal,
+				raw["testWithdefault"], "default value must not be included")
+		})
+	}
+}
diff --git a/openapi3filter/options.go b/openapi3filter/options.go
index 1622339e2..14843dd1b 100644
--- a/openapi3filter/options.go
+++ b/openapi3filter/options.go
@@ -21,4 +21,8 @@ type Options struct {
 
 	// See NoopAuthenticationFunc
 	AuthenticationFunc AuthenticationFunc
+
+	// Indicates whether default values are set in the
+	// request. If true, then they are not set
+	SkipSettingDefaults bool
 }
diff --git a/openapi3filter/validate_request.go b/openapi3filter/validate_request.go
index 4b0bd3413..70b8e8d0a 100644
--- a/openapi3filter/validate_request.go
+++ b/openapi3filter/validate_request.go
@@ -258,7 +258,9 @@ func ValidateRequestBody(ctx context.Context, input *RequestValidationInput, req
 	defaultsSet := false
 	opts := make([]openapi3.SchemaValidationOption, 0, 3) // 3 potential opts here
 	opts = append(opts, openapi3.VisitAsRequest())
-	opts = append(opts, openapi3.DefaultsSet(func() { defaultsSet = true }))
+	if !options.SkipSettingDefaults {
+		opts = append(opts, openapi3.DefaultsSet(func() { defaultsSet = true }))
+	}
 	if options.MultiError {
 		opts = append(opts, openapi3.MultiErrors())
 	}